Durability of Concrete PilesAgnes FerinnaZakaria Niode

Introduction

•Concrete is the most durable material used in constructing piles for non-aggressive environment.

Durability Failure in Concrete Piles

Leaching

Organic Acid & CO2

Ground

Water

Concrete Pile

Disruptive Process

Sulphate

SoilConcrete Pile

Sulphate Ion (SO4-2)

•Sulphate ions available in soil are bound with Magnesium (Mg), Calcium (Ca), Potassium (K) and Sodium (Na).

•The reaction will result in the increase of molecular volume of the minerals and at the end trigger the disintegration of hardened concrete.

SulphateCalcium Aluminat

e

Calcium Sulpho-

aluminate

Silicate Minerals

Magnesium

Sulphate

Ammonium Sulphate

Portland Cement

•Ammonium Sulphate exists unnaturally in soil due to the use of fertilizers and coal-gas byproducts.

Prevention

•Use of high strength pre-cast concrete pile.

•Achieve dense and well-compacted concrete to decrease permeability.

•Application of hot bitumen spray coat, bituminous paint, trowelled-on mastic asphalt, or adhesive plastics sheeting.

•Use of high alumina cement.•Use of super-sulphated cement.

Concrete Piles in Marine•Pre-cast concrete piles are more vulnerable in

marine condition than the cast in-situ concrete piles because cast in-situ concrete piles use a steel shell tube.

•Dense and well-compacted concrete pile should be provided with at least 50-mm concrete cover.

•Disintegration of concrete piles occur intensely at splashing-zone of the pile.

•Cement content = 360 kg/m3 at minimum rate.•Water content ratio = 0,45 at maximum rate.

Structural Design of Steel PilesAgnes FerinnaZakaria Niode

Steel PilesAdvantages Disadvantages

• Robust and light to handle• Capable of carrying high

compressive load when driven on hard stratum

• Capable to develop a high frictional resistance

• Have a good resilience and resistance to buckling and bending forces

• Can be cut and re-trimmed easily

• Expensive• Vulnerable to corrosion

Lifting Method

•There isn’t any specific method for lifting steel pile but the recommended method is to lift the pile ¼ of the length measured from the top part.

•This method is given to achieve safe and quick lifting of the steel pile.

Driving Capacity

Selection of Hammer